I couldn’t find this in the course of my usual patent searching, so here goes…
Today’s invention is robotic suitcases that follow the owner about. The cases each have powered wheels and sensors which allow them to form a (disconnected) line behind the owner -like ducklings (the owner would strap a sensor to his/her ankle).
This would allow rapid movement with more luggage than could be carried.
The spacing between cases could be automatically adjusted to cope with crowd conditions. If they were scattered by pressing crowds, they would automatically reform (like BOIDS) or, if separated by too great a distance, they might stop and issue an alarm.